1. Field of the Invention
The present invention, in general, relates to audio equipment and, more particularly, to audio cables used to supply a signal to speakers and other audio or home theater components.
In any acoustic type of system, such as a stereo or a surround-sound system or a home-theater system or even an amplified live source of music, one or more speakers are required to produce (or reproduce) that sound that is being listened to.
In addition, with any type of an acoustic system the quality of the sound that is ultimately produced is a function of each component of the acoustical system. For example, great speakers will not produce great sound if an inferior amplifier is used. An audio system is like a xe2x80x9cchainxe2x80x9d in which the xe2x80x9cweak linkxe2x80x9d determinesxe2x80x94by way of limitationxe2x80x94the quality of sound that can be produced.
Therefore, the quest for superb quality sound has driven the market inducing it to improve every component of an acoustical system. It has long been known that the audio cables that supply the electrical signal and power from an amplifier to the speakers are critical components.
For example, if the electrical conductors that are used to form the audio cables are too small for the speakers and amplifier that are used, then power will be lost in the audio cables (by way of increased electrical resistance and a resulting voltage drop) and the sound that will be reproduced by the speakers, in particular the lower frequency sounds, will be adversely affected.
Manufacturers are adept at compensating for such needs by offering a variety of sizes for the electrical conductors in the audio cables that they manufacture and in helping audiophiles match the size of the conductors in the audio cables with the power requirements of the acoustical system (also known as an audio system).
However, another limitation that affects the sound quality of the audio system is the quality of the signal that is supplied to the speaker. A speaker is essentially a xe2x80x9cdumbxe2x80x9d transducer. It simply moves in response to the characteristics of the electrical waveform that drives it. It is a linear motor that moves back and forth as a result of magnetic attraction and repulsion. In general, the design and functioning of speakers is well understood in the audio arts.
However, it is important that the electrical waveform that drives each speaker be as perfect or as pure as possible. Deviation away from the ideal is, in general, referred to as xe2x80x9cdistortionxe2x80x9d It is sometimes also called xe2x80x9cnoisexe2x80x9d.
If distortion is present in the waveform, the xe2x80x9cdumbxe2x80x9d speaker, having no way to differentiate distortion apart from music, will simply respond to the distortion that is present in the electrical waveform that is being supplied to it and it will, accordingly, reproduce it. Distortion is not pleasant to listen to.
The electrical components selected for every component, from tuner and preamplifier to power amplifier and including the audio cables that are used are designed to minimize distortion.
However, when an electrical current is being propagated through a conductor various distortions are produced in response to the flow of current through the conductor. These responses include the generation of an electromagnetic field around the audio cables themselves. This effect has been discounted in the past, mostly because audio engineers have been unable to remedy the situation, and also in part because the deleterious effects have not been understood or well appreciated.
However, as the quality of audio systems has improved generally, the resulting sound that is produced by these systems has increasingly become purer. A good (pure) sounding audio system is sometimes referred to as being a xe2x80x9ccleanxe2x80x9d system. The xe2x80x9ccleanerxe2x80x9d the sound has become, the more noticeable have become other sources of distortion, previously not appreciated.
Accordingly, this is currently the reason that both audiophiles and audio design engineers have begun to take note about reducing the distortions that occur in audio cables. Audiophiles are willing to pay a premium to purchase audio cables if they can further ameliorate the deleterious sources of distortion.
The electromagnetic fields that are produced by the audio cables themselves combine with the electromagnetic fields that are produced by the audio cables at various locations along the length of the cable. This is because audio cables are not placed in a perfectly straight line but include curves and sometimes even loops to use up extra cable length.
The electromagnetic fields constructively and destructively interfere with each other and with the original waveform (i.e., the output from the power amplifier). The result is to alter the original electrical waveform before it reaches the speakers and to produce an impure, distorted sound.
The alteration of the original waveform that is supplied to the speakers is another form of distortion that affects the sound quality that is ultimately reproduced by the speakers. This is because the constructive interference produces an electrical waveform to the speaker that is greater than that which the original electrical signal called for. Conversely, any destructive interference produces a waveform that is diminished from that of the original.
The electromagnetic emissions by the audio cables can further interfere with and degrade the performance of other audio components, such as that of the preamplifier, tuner, power amplifier, speakers, etc.
In addition to the electromagnetic interference so produced, there are other anomalous forms of energy that are hypothesized to be produced within the audio cables that emanate therefrom. These energies are not presently well understood, but include perhaps sound and heat and mechanical distortions, and sometimes, it is further speculated, they operate at the molecular level. Additional research, perhaps in the quantum physics arena, will shed more light on the various causes and effects of various energies and their interactions that further contribute to the generation of distortion.
With the present level of limited understanding regarding all of the possible causes, distortion still occurs (for whatever reasons) and it remains desirable to mitigate its effect, especially in audio cables.
Furthermore, electromagnetic interference inherently arises from all sources that consume electrical energy. For example, electromagnetic and perhaps other types of radiation, emanate from each component of an audio system. The electromagnetic energy, for example, that is emitted by the power amplifier radiates out from the power amplifier and enters the conductors in the audio cables, producing further distortion.
The distortion in the audio cables comes, in part, from the components that supply the original waveform and so the original waveform is inherently impure to at least some degree. Additional distortion arises from the electromagnetic emissions (i.e. radiation) from these (and other) components that are, in turn, received by the audio cables. This is because the audio cables function as antennas. While conventional shielding techniques provide some relief they are not effective at limiting distortions that are produced within the audio cable itself.
Another problem with audio cables is that the larger diameter cables are especially difficult to bend sharply. A short radius bend (i.e., a sharp bend) is required when the audio cable is connected to an audio system component, such as to an amplifier or to a speaker. In particular, the presently disclosed invention tends to further increase the diameter of the audio cable. As such, a solution to allow tighter bends in large diameter audio cables is a desirable feature to attain.
Accordingly, there exists today a need for an method and product for reducing noise and distortion in an audio cable, an audio power cable, an audio interconnect, a speaker cable, or any cable or wire that is used in an audio or home theater system to interconnect component parts. Clearly a method and product useful to lessen the distortion that is produced by an audio cable and which can help prevent the audio cable from receiving distortions from other sources is a useful and desirable device.
2. Description of Prior Art
Audio cables are, in general, well known. Increasing the size of the electrical conductor and shielding are presently known methods of reducing distortion in an audio cable.
U.S. Pat. No. 5,814,761 to Piazza that issued on Sep. 29, 1998 deals with a passive EMI dissipation apparatus and method.
While the structural arrangements of the currently known devices and methods, at first appearance, have similarities with the present invention, they differ in material respects. These differences, which will be described in more detail hereinafter, are essential for the effective use of the invention and which admit of the advantages that are not available with the prior devices and methods.
It is an object of the present invention to provide a method and product for reducing distortion in an audio cable that is effective at reducing noise and distortion produced by the audio cable itself.
It is also an important object of the invention to provide a method and product for reducing noise and distortion in an audio cable that is effective at reducing noise and distortion that is produced by other sources and received by the audio cable.
Another object of the invention is to provide a method and product for reducing noise and distortion in an audio cable that is effective at reducing the high frequency electromagnetic energy radiated outward by an audio cable.
Still another object of the invention is to provide a method and product for reducing noise and distortion in an audio cable that is effective at reducing noise and distortion levels that reach a speaker.
Still yet another object of the invention is to provide a method and product for reducing noise and distortion in an audio cable that produces a cleaner sound.
Yet another important object of the invention is to provide a method and product for reducing noise and distortion in an audio cable that is inexpensive to manufacture.
Still yet another important object of the invention is to provide a method and product for reducing noise and distortion in an audio cable that can be readily bent along a radius.
An especially useful object of the invention is to provide a method and product for reducing noise and distortion in an audio cable that provides a termination to an audio cable that can be bent around a tight radius.
A further especially useful object of the invention is to provide a method and product for reducing noise and distortion in an audio cable that facilitates connection of the audio cable to a component of an audio system.
Briefly, a method and product for reducing noise and distortion in an audio cable for use in an sound system that is constructed in accordance with the principles of the present invention has a flexible outer conduit and at least one electrical conductor disposed in the conduit. A granular ferro-electric substance is disposed in the conduit along its longitudinal length. The electrical conductor extends from each end of the cable and may include whatever termination is desired to connect the electrical conductor to a speaker or other component part of an audio or home theater system. A seal is provided at each end of the audio cable to retain the ferro-electric substance. A preferred ferro-electric substance includes generally spherically shaped beads of silica gel that provide improved flexing of the audio cable.